This invention pertains to an improvement in hydraulic pumps and is generically applicable to double-acting simplex plunger pumps of both the "plunger" and "piston" types.
Pertinent prior art includes U.S. Pat. No. 5,173,039 issued to the present applicant Dec. 22, 1992, and U.S. Pat. No. 5,183,396 issued to James E. Cook & O. Harald S.
Erikson on Feb. 2, 1993. The latter patent discloses an alignment means comprising in part check valves for maintaining alignment of a pair of spaced-apart combined-plunger stuffing box and head members, and the reciprocating plunger or piston.
The present invention provides an improvement over the above-mentioned patents by providing a unique self-aligning system for the combined plunger-stuffing box head members and the plunger. My present invention lends itself to much reduced manufacturing costs, as well as higher reliability and precision alignment of the aforesaid parts.